Distributed Authentication and Key Management in Wireless Mesh Networks

Authentication and Key Management (AKM) in Wireless Networks have been addressed in the IEEE 802.11i standard [10]. However, the IEEE 802.11s [21] Wireless Mesh Networks impose some further AKM requirements due to their large scale, distributed functionalities and decentralized authority. According to the IEEE 802.11s specifications, any security solutions should rely on IEEE 802.11i mechanisms. However, considering the architecture and specifications of a Wireless Mesh Network, an adaptation of the 802.11ibased mechanisms and AKM procedures to the new security framework of a Mesh is necessary, especially that IEEE 802.11i has been designed without multi-hop communication and Wireless Mesh Networks in mind. The thesis tackles the AKM mechanisms and protocols that are currently under considerations for possible use inWireless Mesh Networks. It presents a detailed analysis of the different possible AKM schemes. It sheds the light on critical introduced enhancements and modifications with respect to IEEE 802.11i as to fulfill the MAC layer security requirements for Wireless Mesh Networks. Moreover, a Distributed Authorization Model is proposed to ensure AKM efficiency. It allows multiple WMN application scenarios. The scheme is based on PKI mechanisms involving issuing, renewing and revocation of certificates, and it employs a threshold authorization scheme in order to cope with the decentralized nature of Wireless Mesh Networks.